Answer:
Two in a whole and four in a pair. Six in a trio you see. Eight's a quartet but what you must get is the name that fits just one of me.
I am the noise Santa's reindeers make
I must be broken before you can use me.
What can be heard in court or used to carry briefs?
Lighter than feather and softer than silk, yet the strongest man in the world cannot hold me for more than a few minutes. What am I?
Give it food and it will live, give it water and it will die.